为深入分析保护层开采的实施效果,依据煤岩卸压变形理论和瓦斯运移特性,建立保护层开采测评指标体系,并选择淮南矿区对指标现场应用方法进行分析。研究结果表明:测评体系包括保护范围和保护效果两部分,其中,瓦斯压力、瓦斯含量、煤层透气性系数、煤层顶底板相对变形、瓦斯抽放量、突出指标的变化等因素可作为效果考察的现场测评指标。保护层开采后,应首先明确其保护范围,然后再对保护效果分别从煤体力学特性、煤层瓦斯特性和煤层开采动力特性3方面进行综合分析,按照现场实测值与指标临界值的对比,即可系统地定量评价保护层开采的效果。
In order to analyze the implementation results of protection layer mining, according to distortion mechanism of wall rock and moving characteristics of gas, a protection layer exploiting results evaluation index system was brought forward, and locale application methods of evaluation indexes were analyzed in terms of practice in Huainan mining area. Research results indicate that the measure system includes two parts, one is the evaluation of protection scope and the other is protection effect. Such factors as gas pressure, gas content, coal seam permeability coefficient, relative deformation of coal seam roof and floor, gas drainage quantity and the change of outburst indexes can be used as the evaluation indexes in field- work. After starting protective layer mining, the protection scope should be ascertained firstly, and then protection effect can be evaluated in terms of coal physical properties, coal seam gas properties and dynam- ic characteristics in coal mining. The protection layer mining effect can be quantitatively appraised by comparing measured values on site with index thresholds.